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Wendy W J Van De Sande - One of the best experts on this subject based on the ideXlab platform.
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the development of a novel diagnostic pcr for Madurella Mycetomatis using a comparative genome approach
bioRxiv, 2020Co-Authors: Kimberly Eadie, A H Fahal, Sandra Smit, Emmanuel Edwar Siddig, Sarah A Ahmed, Annelies Verbon, Bertrand Nyuykonge, Wendy W J Van De SandeAbstract:Eumycetoma is a neglected tropical disease characterized by large tumorous lesions. It is most commonly caused by the fungus Madurella Mycetomatis which accounts for more than 70% of cases in central Africa. Currently, identification of the causative agent can only be reliably performed by a species-specific PCR. However, we recently demonstrated that our M. Mycetomatis specific PCR can cross-react with Madurella pseudoMycetomatis. We therefore used a comparative genome approach to develop a new M. Mycetomatis specific PCR for species identification. For this we compared the published M. Mycetomatis genome to genomes of other organisms in BLASTCLUST to identify unique M. Mycetomatis predicted protein coding sequences. Based on 16 of these unique sequences, PCR primers were developed. The specificity of these primers was further evaluated in other eumycetoma causing agents including the Madurella sibling species. Out of the 16 tested sequences, only one was unique for M. Mycetomatis and this should be used as a novel diagnostic marker for M. Mycetomatis.
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proteomic analysis of the processes leading to Madurella Mycetomatis grain formation in galleria mellonella larvae
PLOS Neglected Tropical Diseases, 2020Co-Authors: Gerard Sheehan, A H Fahal, Kevin Kavanagh, Mickey Konings, Wendy W J Van De SandeAbstract:Mycetoma is a neglected chronic and granulomatous infection primarily associated with the fungal pathogen Madurella Mycetomatis. Characteristic of this infection is the formation of grains. However, the processes leading to grain formation are not known. In this study, we employed a proteomic approach to characterise M. Mycetomatis grain formation in Galleria mellonella larvae and map the processes leading to grain formation over time. For this, at 1 day, 3 days and 7 days post-inoculation, proteins from grains and hemolymph were extracted and analysed by label-free mass spectrometry. A total of 87, 51 and 48 M. Mycetomatis proteins and 713, 997, 18 G. mellonella proteins were found in grains on day 1, 3 and 7 post-inoculation respectively. M. Mycetomatis proteins were mainly involved in cellular metabolic processes and numerous enzymes were encountered. G. mellonella proteins were primarily involved in the nodulation process. The proteins identified were linked to nodulation and grain formation and four steps of grain formation were identified. The results of this proteomic approach could in the future be used to design novel strategies to interfere with mycetoma grain formation and to combat this difficult to treat infection.
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Madurella Mycetomatis the main causative agent of eumycetoma is highly susceptible to olorofim
Journal of Antimicrobial Chemotherapy, 2020Co-Authors: Kimberly Eadie, A H Fahal, Annelies Verbon, Mickey Konings, Bart J A Rijnders, Jason David Oliver, Mike Birch, Wendy W J Van De SandeAbstract:OBJECTIVES: Eumycetoma is currently treated with a combination of itraconazole therapy and surgery, with limited success. Recently, olorofim, the lead candidate of the orotomides, a novel class of antifungal agents, entered a Phase II trial for the treatment of invasive fungal infections. Here we determined the activity of olorofim against Madurella Mycetomatis, the main causative agent of eumycetoma. METHODS: Activity of olorofim against M. Mycetomatis was determined by in silico comparison of the target gene, dihydroorotate dehydrogenase (DHODH), and in vitro susceptibility testing. We also investigated the in vitro interaction between olorofim and itraconazole against M. Mycetomatis. RESULTS: M. Mycetomatis and Aspergillus fumigatus share six out of seven predicted binding residues in their DHODH DNA sequence, predicting susceptibility to olorofim. Olorofim demonstrated excellent potency against M. Mycetomatis in vivo with MICs ranging from 0.004 to 0.125 mg/L and an MIC90 of 0.063 mg/L. Olorofim MICs were mostly one dilution step lower than the itraconazole MICs. In vitro interaction studies demonstrated that olorofim and itraconazole work indifferently when combined. CONCLUSIONS: We demonstrated olorofim has potent in vitro activity against M. Mycetomatis and should be further evaluated in vivo as a treatment option for this disease.
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The Accuracy of Histopathological and Cytopathological Techniques in the Identification of the Mycetoma Causative Agents
PLOS Neglected Tropical Diseases, 2019Co-Authors: Emmanuel Edwar Siddig, Wendy W J Van De Sande, Najwa A Mhmoud, Sahar Mubarak Bakhiet, Omnia Babekir Abdallah, Salwa O Mekki, Nadia I. El Dawi, Ahmed Hassan FahalAbstract:Mycetoma is a devastating neglected tropical disease, caused by various fungal and bacterial pathogens. Correct diagnosis to the species level is mandatory for proper treatment. In endemic areas, various diagnostic tests and techniques are in use to achieve that, and that includes grain culture, surgical biopsy histopathological examination, fine needle aspiration cytological (FNAC) examination and in certain centres molecular diagnosis such as PCR. In this retrospective study, the sensitivity, specificity and diagnostic accuracy of grain culture, surgical biopsy histopathological examination and FNAC to identify the mycetoma causative organisms were determined. The histopathological examination appeared to have better sensitivity and specificity. The histological examination results were correct in 714 (97.5%) out of 750 patients infected with Madurella Mycetomatis, in 133 (93.6%) out of 142 patients infected with Streptomyces somaliensis, in 53 (74.6%) out of 71 patients infected with Actinomadura madurae and in 12 (75%) out of 16 patients infected with Actinomadura pelletierii. FNAC results were correct in 604 (80.5%) out of 750 patients with Madurella Mycetomatis eumycetoma, in 50 (37.5%) out of 133 Streptomyces somaliensis patients, 43 (60.5%) out of 71 Actinomadura madurae patients and 11 (68.7%) out of 16 Actinomadura pelletierii. The mean time required to obtain the FNAC result was one day, and for the histopathological examinations results it was 3.5 days, and for grain it was a mean of 16 days. In conclusion, histopathological examination and FNAC are more practical techniques for rapid species identification than grain culture in many endemic regions.
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vntr confirms the heterogeneity of Madurella Mycetomatis and is a promising typing tool for this mycetoma causing agent
Medical Mycology, 2019Co-Authors: Kimberly Eadie, A H Fahal, Sarah A Ahmed, Deborah Horstkreft, Wendy W J Van De SandeAbstract:The neglected tropical disease mycetoma is a chronic granulomatous inflammatory and infectious disease affecting various body parts. The most common causative agent is the fungus Madurella Mycetomatis. In order to study the genetic diversity of this fungus and to monitor any potential outbreaks, a good typing method that can be used in endemic settings is needed. Previous typing methods developed were not discriminative and not easy to perform in resource-limited laboratories. Variable-Number-Tandem-Repeat (VNTR) typing overcomes these difficulties and further enables interlaboratory data comparison. Therefore, in this study we developed a VNTR method for typing M. Mycetomatis. Six tandem-repeats were identified in the genome of M. Mycetomatis isolate MM55 using an online tandem repeats software. The variation in these repeats was determined by PCR and gel-electrophoresis on DNA obtained from 81 M. Mycetomatis isolates obtained from patients. These patients originated from Sudan, Mali, Peru, and India. The 81 isolates were divided into 14 genotypes which separated into two main clusters with seven and five subdivisions, respectively. VNTR typing confirms the heterogeneity of M. Mycetomatis strains and can be used to study the epidemiology of M. Mycetomatis. The results presented in this article are made fully available to the scientific community on request from the Eumycetoma Working Group. We hope that this open resource approach will bridge scientific community working with mycetoma from all around the world and lead to a deeper understanding of M. Mycetomatis.
A H Fahal - One of the best experts on this subject based on the ideXlab platform.
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draft genome sequences of three clinical isolates of Madurella Mycetomatis the major cause of black grain mycetoma
Microbiology resource announcements, 2020Co-Authors: El Shiekh Khidir, A H Fahal, Abdalla Ahmed, Al Amin IbrahimAbstract:ABSTRACT The draft genomes of three fungal clinical isolates of Madurella Mycetomatis from patients with mycetoma are presented. No finished genome is currently available for this important fungus. Therefore, the addition of these new draft genomes will help us better understand the diversity and pathogenicity of this important species.
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the development of a novel diagnostic pcr for Madurella Mycetomatis using a comparative genome approach
bioRxiv, 2020Co-Authors: Kimberly Eadie, A H Fahal, Sandra Smit, Emmanuel Edwar Siddig, Sarah A Ahmed, Annelies Verbon, Bertrand Nyuykonge, Wendy W J Van De SandeAbstract:Eumycetoma is a neglected tropical disease characterized by large tumorous lesions. It is most commonly caused by the fungus Madurella Mycetomatis which accounts for more than 70% of cases in central Africa. Currently, identification of the causative agent can only be reliably performed by a species-specific PCR. However, we recently demonstrated that our M. Mycetomatis specific PCR can cross-react with Madurella pseudoMycetomatis. We therefore used a comparative genome approach to develop a new M. Mycetomatis specific PCR for species identification. For this we compared the published M. Mycetomatis genome to genomes of other organisms in BLASTCLUST to identify unique M. Mycetomatis predicted protein coding sequences. Based on 16 of these unique sequences, PCR primers were developed. The specificity of these primers was further evaluated in other eumycetoma causing agents including the Madurella sibling species. Out of the 16 tested sequences, only one was unique for M. Mycetomatis and this should be used as a novel diagnostic marker for M. Mycetomatis.
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proteomic analysis of the processes leading to Madurella Mycetomatis grain formation in galleria mellonella larvae
PLOS Neglected Tropical Diseases, 2020Co-Authors: Gerard Sheehan, A H Fahal, Kevin Kavanagh, Mickey Konings, Wendy W J Van De SandeAbstract:Mycetoma is a neglected chronic and granulomatous infection primarily associated with the fungal pathogen Madurella Mycetomatis. Characteristic of this infection is the formation of grains. However, the processes leading to grain formation are not known. In this study, we employed a proteomic approach to characterise M. Mycetomatis grain formation in Galleria mellonella larvae and map the processes leading to grain formation over time. For this, at 1 day, 3 days and 7 days post-inoculation, proteins from grains and hemolymph were extracted and analysed by label-free mass spectrometry. A total of 87, 51 and 48 M. Mycetomatis proteins and 713, 997, 18 G. mellonella proteins were found in grains on day 1, 3 and 7 post-inoculation respectively. M. Mycetomatis proteins were mainly involved in cellular metabolic processes and numerous enzymes were encountered. G. mellonella proteins were primarily involved in the nodulation process. The proteins identified were linked to nodulation and grain formation and four steps of grain formation were identified. The results of this proteomic approach could in the future be used to design novel strategies to interfere with mycetoma grain formation and to combat this difficult to treat infection.
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Madurella Mycetomatis the main causative agent of eumycetoma is highly susceptible to olorofim
Journal of Antimicrobial Chemotherapy, 2020Co-Authors: Kimberly Eadie, A H Fahal, Annelies Verbon, Mickey Konings, Bart J A Rijnders, Jason David Oliver, Mike Birch, Wendy W J Van De SandeAbstract:OBJECTIVES: Eumycetoma is currently treated with a combination of itraconazole therapy and surgery, with limited success. Recently, olorofim, the lead candidate of the orotomides, a novel class of antifungal agents, entered a Phase II trial for the treatment of invasive fungal infections. Here we determined the activity of olorofim against Madurella Mycetomatis, the main causative agent of eumycetoma. METHODS: Activity of olorofim against M. Mycetomatis was determined by in silico comparison of the target gene, dihydroorotate dehydrogenase (DHODH), and in vitro susceptibility testing. We also investigated the in vitro interaction between olorofim and itraconazole against M. Mycetomatis. RESULTS: M. Mycetomatis and Aspergillus fumigatus share six out of seven predicted binding residues in their DHODH DNA sequence, predicting susceptibility to olorofim. Olorofim demonstrated excellent potency against M. Mycetomatis in vivo with MICs ranging from 0.004 to 0.125 mg/L and an MIC90 of 0.063 mg/L. Olorofim MICs were mostly one dilution step lower than the itraconazole MICs. In vitro interaction studies demonstrated that olorofim and itraconazole work indifferently when combined. CONCLUSIONS: We demonstrated olorofim has potent in vitro activity against M. Mycetomatis and should be further evaluated in vivo as a treatment option for this disease.
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pyomelanin secretion in Madurella Mycetomatis interferes with spectrophotometric endpoint reading using the sensititre yeastone alamarblue assay but not with visual endpoint reading
Antimicrobial Agents and Chemotherapy, 2019Co-Authors: B Nyuykonge, A H Fahal, P D Croughs, Annelies Verbon, W W J Van De SandeAbstract:The use of the Sensititre YeastOne YO10 alamarBlue assay for the in vitro susceptibility testing of Madurella Mycetomatis was evaluated in M. Mycetomatis isolates with and without pyomelanin secretion. Pyomelanin secretion did not influence visual endpoint reading; however, it caused a shift in peak absorbance from 570 nm to 620 nm when read spectrophotometrically. Therefore, when choosing the method for endpoint reading, the presence of pyomelanin should be considered.
Alex Van Belkum - One of the best experts on this subject based on the ideXlab platform.
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genome sequence of Madurella Mycetomatis mm55 isolated from a human mycetoma case in sudan
Genome Announcements, 2016Co-Authors: Sandra Smit, A H Fahal, Alex Van Belkum, Martijn F L Derks, Sander Bervoets, Willem B Van Leeuwen, Wendy W J Van De SandeAbstract:textabstractWe present the first genome sequence for a strain of the main mycetoma causative agent, Madurella Mycetomatis. This 36.7-Mb genome sequence will offer new insights into the pathogenesis of mycetoma, and it will contribute to the development of better therapies for this neglected tropical disease.
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fructose bisphosphate aldolase and pyruvate kinase two novel immunogens in Madurella Mycetomatis
Medical Mycology, 2012Co-Authors: Nele De Klerk, A H Fahal, Alex Van Belkum, Corne P De Vogel, Wendy W J Van De SandeAbstract:Eumycetoma, a chronic granulomatous disease characterized by a subcutaneous mass, multiple sinuses and purulent discharge containing grains, remains diffi cult to diagnose and treat. Madurella Mycetomatis is the most common causative agent of eumycetoma. Using a serum pool from patients with active mycetoma, we screened a M. Mycetomatis specifi c λ gt11 cDNA library which was shown to contain 8% of cDNA inserts encoding proteins involved in glycolysis. Two of these enzymes, fructose-bisphosphate aldolase (FBA) and pyruvate kinase (PK), were produced in vitro and their antigenicity was studied with bead-based fl ow cytometry. It appeared that both FBA and PK IgG antibodies were present in eumycetoma patient sera. However, only FBA antibody levels were found to be signifi cantly higher in eumycetoma patient sera when compared to healthy Sudanese controls. Furthermore, FBA and PK were also found to be expressed on the hyphae present in the mycetoma grain. In conclusion, this study presents two new antigenic proteins of M. Mycetomatis next to the translationally controlled tumour protein (TCTP): the glycolytic enzymes FBA and PK. These antigens might be useful as vaccine-candidates in the prevention of mycetoma.
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in vitro susceptibility of Madurella Mycetomatis to posaconazole and terbinafine
Antimicrobial Agents and Chemotherapy, 2011Co-Authors: Alex Van Belkum, A H Fahal, Wendy W J Van De SandeAbstract:ABSTRACT Presently, therapy of eumycetoma in Sudan is still based on surgery combined with prolonged ketoconazole therapy. This usually results in a poor clinical outcome. To determine if posaconazole and terbinafine could offer better therapeutic alternatives, the in vitro susceptibilities of 34 Madurella Mycetomatis strains were determined. It appeared that posaconazole was highly active against M. Mycetomatis but terbinafine was only moderately active. Since posaconazole has an excellent safety profile, it might provide an important alternative in mycetoma therapy.
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polymorphisms in catechol o methyltransferase and cytochrome p450 subfamily 19 genes predispose towards Madurella Mycetomatis induced mycetoma susceptibility
Medical Mycology, 2010Co-Authors: Wendy W J Van De Sande, A H Fahal, Mehri Tavakol, Alex Van BelkumAbstract:Mycetoma caused by Madurella Mycetomatis is a devastating and neglected disease which primarily affects males. Since this predominance cannot be easily explained by behaviour differences between men and women, other factors, including sex hormones, could be the cause. To monitor for possible defi ciencies in hormone synthesis among mycetoma patients, we investigated the types and allele frequencies of the genes encoding for catechol-O-methyltransferase (COMT), cytochrome p450 subfamily 1 (CYP1B1), cytochrome p450 subfamily 17 (CYP17), cytochrome p450 subfamily 19 (CYP19) and hydroxysteroid dehydrogenase 3B (HSD3B). Signifi cant differences in allele distribution were demonstrated for CYP19 ( P � 0.004) and COMT ( P � 0.005), as well as gender dimorphism for both CYP19 and COMT polymorphisms. The COMT polymorphism was associated with lesion size. The genotypes obtained for COMT and CYP19 were connected with higher 17β-estradiol production, which was confi rmed by signifi cantly elevated serum levels of 17β-estradiol in male patients. In contrast, lowered levels of dehydroepiandrosteron (DHEA) were found in mycetoma patients. The in vitro growth of M. Mycetomatis was not infl uenced by 17β-estradiol, progesterone, DHEA and testosterone. The differences in hormone levels we noted between mycetoma patients and healthy controls did not directly affect the fungus itself. Indirect effects on the patients’ hormone regulated immune states are the more likely explanations for mycetoma susceptibility.
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Madurella Mycetomatis is not susceptible to the echinocandin class of antifungal agents
Antimicrobial Agents and Chemotherapy, 2010Co-Authors: Wendy W J Van De Sande, A H Fahal, Irma A J M Bakkerwoudenberg, Alex Van BelkumAbstract:Eumycetoma is a subcutaneous disease caused by a variety of microorganisms, both bacteria and fungi. The most common causative fungus is Madurella Mycetomatis. After surgical debridement, eumycetoma is usually treated for extended periods of time with high doses of either itraconazole (ITZ) or ketoconazole (KTZ), which can result in hepatoxicity. In order to identify alternative antifungal therapies, the susceptibilities of M. Mycetomatis to other antifungal agents (amphotericin B, 5-flucytosine, fluconazole, and voriconazole) have been determined before and compared to the obtained susceptibilities to ITZ and KTZ. M. Mycetomatis remains most susceptible toward the azoles and amphotericin B; no activity was seen with
Abdalla O A Ahmed - One of the best experts on this subject based on the ideXlab platform.
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melanin biosynthesis in Madurella Mycetomatis and its effect on susceptibility to itraconazole and ketoconazole
Microbes and Infection, 2007Co-Authors: Wendy W J Van De Sande, A H Fahal, Abdalla O A Ahmed, Henri A Verbrugh, Jojanneke M C Coppens, Alex Van BelkumAbstract:One of the hallmarks of eumycetoma is the formation of fungal grains, which are secreted by multiple sinuses in infected tissues. Madurella Mycetomatis grains are black. This black colour was shown to be due to the presence of melanin. Melanin can be produced through various biochemical pathways. It appeared that M. Mycetomatis melanisation could be blocked by inhibitors of the pyo- and dihydroxynaphthalene (DHN)-melanin pathways but not by inhibitors of the dihydroxyphenylalanine (L-DOPA)-melanin pathway. Melanin isolated from M. Mycetomatis cells provides in vitro protection against the killing effects of the oxidant permanganate and several antifungals. When melanin was added to the culture medium, MICs were found to be 16-fold elevated in the case of itraconazole and 32-fold for ketoconazole. MICs for amphotericin B, fluconazole and voriconazole were not affected. Since itraconazole and ketoconazole are the main antifungal agents used to treat mycetoma, the clinical relevance of the in vitro rise in MIC should be studied further.
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translationally controlled tumor protein from Madurella Mycetomatis a marker for tumorous mycetoma progression
Journal of Immunology, 2006Co-Authors: Wendy W J Van De Sande, Abdalla O A Ahmed, Henri A Verbrugh, Dirkjan Janse, Vishal Hira, Heidy Goedhart, Alex Van BelkumAbstract:About 40 years ago Abs against the fungus Madurella Mycetomatis were first demonstrated to be present in eumycetoma patients, a disease characterized by tumorous swellings. To date nothing is known about the individual immunoreactive Ags present in this fungus. In the present study, we identify its first immunogenic Ag, a protein homologous to the translationally controlled tumor protein (TCTP), a well-conserved histamine release factor in a range of eukaryotes. The gene for this Ag was demonstrated to be present in two variants in M. Mycetomatis , with 13% aa difference between the two proteins encoded. In vitro, TCTP was secreted into the culture medium. In vivo, it was found to be expressed on hyphae present in developing stages of the eumycetoma-characteristic black grain. Significant IgG and IgM immune responses, against the whole protein and selected M. Mycetomatis- specific peptides, were determined. The Ab levels correlated with lesion size and disease duration. Overall, the patients with the largest lesions had the highest Ab level, which lowered with decreasing size of the lesion. After 6–15 years of disease duration the Ab levels were the highest. TCTP is the first well-characterized immunogenic Ag, simultaneously the first monomolecular vaccine candidate, identified for the fungus M. Mycetomatis .
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genotyping of Madurella Mycetomatis by selective amplification of restriction fragments amplified fragment length polymorphism and subtype correlation with geographical origin and lesion size
Journal of Clinical Microbiology, 2005Co-Authors: Wendy W J Van De Sande, Abdalla O A Ahmed, Henri A Verbrugh, Roy Gorkink, Guus Simons, Alex Van BelkumAbstract:One of the causative organisms of mycetoma is the fungus Madurella Mycetomatis. Previously, extensive molecular typing studies identified Sudanese isolates of this fungus as clonal, but polymorphic genetic markers have not yet been identified. Here, we report on the selective amplification of restriction fragment (AFLP) analysis of 37 Sudanese clinical isolates of M. Mycetomatis. Of 93 AFLP fragments generated, 25 were polymorphic, and 12 of these 25 polymorphic fragments were found in a large fraction of the strains. Comparative analysis resulted into a tree, composed of two main (clusters I and II) and one minor cluster (cluster III). Seventy-five percent of the strains found in cluster I originated from central Sudan, while the origin of the strains in cluster II was more heterogeneous. Furthermore, the strains found in cluster I were generally obtained from lesions larger than those from which the strains found in cluster II were obtained (chi-square test for trend, P = 0.03). Among the 12 more commonly found polymorphisms, 4 showed sequence homology with known genes. Marker A7 was homologous to an endo-1,4-beta-glucanase from Aspergillus oryzae, 97% identical markers A12 and B3 matched a hypothetical protein from Gibberella zeae, and marker B4 was homologous to casein kinase I from Danio rerio. The last marker seemed to be associated with strains originating from central Sudan (P = 0.001). This is the first report on a genotypic study where genetic markers which may be used to study pathogenicity in M. Mycetomatis were obtained.
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testing of the in vitro susceptibilities of Madurella Mycetomatis to six antifungal agents by using the sensititre system in comparison with a viability based 2 3 bis 2 methoxy 4 nitro 5 sulfophenyl 5 phenylamino carbonyl 2h tetrazolium hydroxide xtt
Antimicrobial Agents and Chemotherapy, 2005Co-Authors: Wendy W J Van De Sande, Abdalla O A Ahmed, Irma A J M Bakkerwoudenberg, Ad Luijendijk, Alex Van BelkumAbstract:The in vitro susceptibilities of 36 clinical isolates of Madurella Mycetomatis , the prime agent of eumycetoma in Africa, to ketoconazole, itraconazole, fluconazole, voriconazole, amphotericin B, and flucytosine were determined by the Sensititre YeastOne system. This system appeared to be a rapid and easy test, and by use of hyphal suspensions it generated results comparable to those of a modified NCCLS method. After 10 days of incubation, the antifungal activities of ketoconazole (MIC at which 90% of isolates were inhibited [MIC 90 ], 0.125 μg/ml), itraconazole (MIC 90 , 0.064 μg/ml), and voriconazole (MIC 90 , 0.125 μg/ml) appeared superior to those of fluconazole (MIC 90 , 128 μg/ml) and amphotericin B (MIC 90 , 1 μg/ml), with MICs in the clinically relevant range. All isolates were resistant to flucytosine (all MICs above 64 μg/ml). Based on the relatively broad range of MICs obtained for the antifungal agents, routine testing of M. Mycetomatis isolates for susceptibility to antifungal agents seems to be relevant to adequate therapeutic management.
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mycetoma caused by Madurella Mycetomatis a neglected infectious burden
Lancet Infectious Diseases, 2004Co-Authors: Abdalla O A Ahmed, A H Fahal, Wendy W J Van De Sande, Willem B Van Leeuwen, Henri A Verbrugh, Alex Van BelkumAbstract:Tropical eumycetoma is frequently caused by the fungus Madurella Mycetomatis. The disease is characterised by extensive subcutaneous masses, usually with sinuses draining pus, blood, and fungal grains. The disease affects individuals of all ages, although disability is most severe in adults who work outdoors. Compared with major diseases such as tuberculosis, malaria, and HIV, disease from M Mycetomatis is underestimated but socioeconomically important. Many scientific case reports on mycetoma exist, but fundamental research was lacking until recently. We present a review on developments in the clinical, epidemiological, and diagnostic management of M Mycetomatis eumycetoma. We describe newly developed molecular diagnostic and gene typing procedures, and their application for management of patients and environmental research. Fungal susceptibility tests have been developed as well as a mouse model of infection. These advances should greatly further our understanding of the molecular basis of eumycetoma.
Henri A Verbrugh - One of the best experts on this subject based on the ideXlab platform.
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A Polymorphism in the Chitotriosidase Gene Associated with Risk of Mycetoma Due to Madurella Mycetomatis Mycetoma–A Retrospective Study
PLOS Neglected Tropical Diseases, 2015Co-Authors: Patricia E B Verwer, Ahmed Hassan Fahal, Henri A Verbrugh, Kimberly Eadie, Charlotte C Notenboom, Wendy W J Van De SandeAbstract:textabstractBackground: Madurella Mycetomatis is the most prevalent causative agent of eumycetoma in Sudan, an infection characterized by the formation of grains. Many patients are exposed to the causative agent, however only a small number develop infection. M. Mycetomatis contains chitin in its cell wall, which can trigger the human immune system. Polymorphisms in the genes encoding for the chitin-degrading enzymes chitotriosidase and AMCase were described, resulting in altered chitinase activity. We investigated the association between 4 of these polymorphisms and the incidence of M. Mycetomatis mycetoma in a Sudanese population. Methodology: Polymorphisms studied in 112 eumycetoma patients and 103 matched controls included a 24-bp insertion in the chitotriosidase gene (rs3831317), resulting in impaired chitinase activity and single nucleotide polymorphism (SNP) in the AMCase gene (rs61756687), resulting in decreased AMCase activity. Also, a SNP (rs41282492) and a 10-bp insertion in the 5’UTR region of the AMCase gene (rs143789088) were studied, both resulting in increased AMCase activity. DNA was isolated from blood and genotypes were determined using PCR-RFLP. Principal Findings: Histological staining proved the presence of chitin in the fungal grain. The polymorphism resulting in decreased chitotriosidase activity was associated with increased odds of eumycetoma (odds ratio 2.9; p = 0.004). No association was found for the polymorphisms in the genes for AMCase (all p>0.05). Conclusion: Decreased chitotriosidase activity was associated with increased risk of M. Mycetomatis mycetoma.
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a polymorphism in the chitotriosidase gene associated with risk of mycetoma due to Madurella Mycetomatis mycetoma a retrospective study
PLOS Neglected Tropical Diseases, 2015Co-Authors: Patricia E B Verwer, A H Fahal, Henri A Verbrugh, Kimberly Eadie, Charlotte C Notenboom, Wendy W J Van De SandeAbstract:textabstractBackground: Madurella Mycetomatis is the most prevalent causative agent of eumycetoma in Sudan, an infection characterized by the formation of grains. Many patients are exposed to the causative agent, however only a small number develop infection. M. Mycetomatis contains chitin in its cell wall, which can trigger the human immune system. Polymorphisms in the genes encoding for the chitin-degrading enzymes chitotriosidase and AMCase were described, resulting in altered chitinase activity. We investigated the association between 4 of these polymorphisms and the incidence of M. Mycetomatis mycetoma in a Sudanese population. Methodology: Polymorphisms studied in 112 eumycetoma patients and 103 matched controls included a 24-bp insertion in the chitotriosidase gene (rs3831317), resulting in impaired chitinase activity and single nucleotide polymorphism (SNP) in the AMCase gene (rs61756687), resulting in decreased AMCase activity. Also, a SNP (rs41282492) and a 10-bp insertion in the 5’UTR region of the AMCase gene (rs143789088) were studied, both resulting in increased AMCase activity. DNA was isolated from blood and genotypes were determined using PCR-RFLP. Principal Findings: Histological staining proved the presence of chitin in the fungal grain. The polymorphism resulting in decreased chitotriosidase activity was associated with increased odds of eumycetoma (odds ratio 2.9; p = 0.004). No association was found for the polymorphisms in the genes for AMCase (all p>0.05). Conclusion: Decreased chitotriosidase activity was associated with increased risk of M. Mycetomatis mycetoma.
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melanin biosynthesis in Madurella Mycetomatis and its effect on susceptibility to itraconazole and ketoconazole
Microbes and Infection, 2007Co-Authors: Wendy W J Van De Sande, A H Fahal, Abdalla O A Ahmed, Henri A Verbrugh, Jojanneke M C Coppens, Alex Van BelkumAbstract:One of the hallmarks of eumycetoma is the formation of fungal grains, which are secreted by multiple sinuses in infected tissues. Madurella Mycetomatis grains are black. This black colour was shown to be due to the presence of melanin. Melanin can be produced through various biochemical pathways. It appeared that M. Mycetomatis melanisation could be blocked by inhibitors of the pyo- and dihydroxynaphthalene (DHN)-melanin pathways but not by inhibitors of the dihydroxyphenylalanine (L-DOPA)-melanin pathway. Melanin isolated from M. Mycetomatis cells provides in vitro protection against the killing effects of the oxidant permanganate and several antifungals. When melanin was added to the culture medium, MICs were found to be 16-fold elevated in the case of itraconazole and 32-fold for ketoconazole. MICs for amphotericin B, fluconazole and voriconazole were not affected. Since itraconazole and ketoconazole are the main antifungal agents used to treat mycetoma, the clinical relevance of the in vitro rise in MIC should be studied further.
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in vitro susceptibility of Madurella Mycetomatis prime agent of madura foot to tea tree oil and artemisinin
Journal of Antimicrobial Chemotherapy, 2007Co-Authors: Wendy W J Van De Sande, A H Fahal, Henri A Verbrugh, Thomas V Riley, Alex Van BelkumAbstract:Objectives: Eumycetoma caused by Madurella Mycetomatis is treated with surgery and high doses of itraconazole and ketoconazole. These agents are toxic, and new therapies are required. Methods: MICs were determined for artemisinin and tea tree oil, two natural herbal compounds. Results: Artemisinin was not active against M. Mycetomatis, but tea tree oil did inhibit its growth. Since tea tree oil's prime component easily penetrates the skin, tea tree oil could be a useful agent in the treatment of eumycetoma. Conclusions: Tea tree oil is active in vitro against M. Mycetomatis.
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translationally controlled tumor protein from Madurella Mycetomatis a marker for tumorous mycetoma progression
Journal of Immunology, 2006Co-Authors: Wendy W J Van De Sande, Abdalla O A Ahmed, Henri A Verbrugh, Dirkjan Janse, Vishal Hira, Heidy Goedhart, Alex Van BelkumAbstract:About 40 years ago Abs against the fungus Madurella Mycetomatis were first demonstrated to be present in eumycetoma patients, a disease characterized by tumorous swellings. To date nothing is known about the individual immunoreactive Ags present in this fungus. In the present study, we identify its first immunogenic Ag, a protein homologous to the translationally controlled tumor protein (TCTP), a well-conserved histamine release factor in a range of eukaryotes. The gene for this Ag was demonstrated to be present in two variants in M. Mycetomatis , with 13% aa difference between the two proteins encoded. In vitro, TCTP was secreted into the culture medium. In vivo, it was found to be expressed on hyphae present in developing stages of the eumycetoma-characteristic black grain. Significant IgG and IgM immune responses, against the whole protein and selected M. Mycetomatis- specific peptides, were determined. The Ab levels correlated with lesion size and disease duration. Overall, the patients with the largest lesions had the highest Ab level, which lowered with decreasing size of the lesion. After 6–15 years of disease duration the Ab levels were the highest. TCTP is the first well-characterized immunogenic Ag, simultaneously the first monomolecular vaccine candidate, identified for the fungus M. Mycetomatis .
